The present invention relates to a tie-down apparatus for structures, and more specifically a tie-down apparatus formed integral with the structure, including especially mobile home structures.
During high wind conditions, e.g., hurricanes and tornadoes, the roof of a building structure can be separated from the structural walls due to the lifting forces created as the wind passes over the roof at very high speeds. Obviously, serious damage occurs to a building and its contents when the roof separates from the building. In geographic areas where high winds are prevalent, the trend has been to utilize additional roof supporting mechanisms beyond that provided when the structure is constructed.
Mobile homes are especially susceptible to damage and destruction during high wind conditions. Hurricane force winds exert two force components on a mobile home. First, the structure takes a pounding from direct wind contact against a relatively flat surface. Second, as the wind is forced around and up the structural walls on the windward side, a vacuum is created on the opposing or leeward side. Since most mobile homes have an open crawl space below the floor surface and less structural integrity, compared to a structure constructed on site, these two force components can create a potentially destructive situation.
Typical hurricane protection for mobile homes involves the use of anchors and tie-down cables spaced around the structural walls and firmly anchored within the adjacent ground area. Another external structure for protecting mobile homes comprises a net anchored to metal beams that stand vertically against the walls of the home and surround the entire structure. Steel cables tie the beams together and also anchor them to the ground. The net placed over the roof increases the roof wind resistance and lowers the probability of roof lift.
A mobile home or other structure is protected against wind damage, especially roof lift, according to the anchoring system of the present invention. During construction of the mobile home, a plurality of parallel channels are formed within the roof and walls structural members, in one embodiment running from one side of the mobile home across the roof to the opposing side. A chain or cable is placed within the channel and each end is terminated with a hook or anchoring device. Anchor bolts are placed in the ground below the perimeter walls of the mobile home and the hook devices are releasably engaged with the ground anchors. Each of the cables is also attached to a ratcheted axle for applying a tension force to the cables, and thus a downwardly directed force on the roof. The cables can be tensioned after the mobile home is moved into place or only when a high wind storm is expected, thereby avoiding excessive roof forces during normal weather conditions.